Bridge for stringed instruments



No. 6l5,053. Patented Nov. 29, l898 L. UTT.

BRIDGE FOR STRINEED INSTRUMENTS.

A lication filed Dec. 13, 1897.)

(No Model.)

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/ l V I UNITED STATES PATENT OFFICE LINCOLN UTT, OF LEXINGTON, MISSOURI.

BRIDGE FOR STRINGED INSTRUMENTS.

SPECIFICATION forming part of Letters Patent No. 61 5,053, dated November 29, 1898.

Application filed December 13, 1897. Serial No. 661,646. (No model.)

To all whom it may concern:

Be it known that I, LINCOLN U'r'r, a citize of the United States, residing at Lexington, in the county of Lafayette and State of Missouri, have invented a new and useful Bridge for Stringed Instruments, of which the following is a specification.

My invention relates to a bridge for stringed instruments of the guitar class, and has for its object to provide a bridge of improved construct-ion having string-rests adapted by their relative positions to compensate for the varying elasticities of the strings.

It is well known that different strings vary in elasticity, and hence that the additional strain applied to the strings in order to bring them into contact with a fret raises the pitches of those strings to different extents. The test of this is that when a string of an instrument of the class to which my invention belongs is touched at the twelfth fret it produces a harmonic octave, which should be accurately attuned with the octave produced by the same string when it is depressed into contact with said twelfth fret; but strings of the same length but difierent elasticities will not produce this accurate relation between the harmonic and normal or fretted octaves for the reason that the string of less elasticity will resist to a greater extent the pressure necessary to bring it into contact with the fret, and hence the normal or fretted octave will be higher in pitch than the harmonic octave. In order to overcome this inconvenience and at the same time avoid the use of crooked frets or frets which do not extend transversely across the finger-board or neck of the instrument, I have devised a bridge having string-rests which are arranged out of transverse alinement, and thus provide for supporting the strings with operative or vibratory lengths of different extentthat is, I have provided a bridge whereby the exposed length of a string of less elasticity is greater than the exposed length of a string of greater elasticity, whereby the resistance ofiered by all of the strings on the same instrument is the same in bringing the several strings into contact with a given fret. In order that the operative lengths of the strings may be varied, however, to suit the particular strings which are applied to the instrument, I have found it desirable to employa bridge having adjustable string-rests which are manually movable in directions parallel with the strings 5 5 and are capable of independent manual adjustment. It is obvious that no fixed scale of elasticity can be assumed as existing between the several strings of an instrument of this class, and therefore the only accurate means which I have discovered for providing the proper exposure of a string is that by which the string-rest may be varied in position. I have found, furthermore, that the adjustment of the exposed or operative length 65 of a string may be accomplished solelythrough the use of a bridge having movable stringrests located near the tailpiece of the instru ment, but that an increased facility of adjustment can be secured by the employment of an auxiliary bridge located on the neck of the instrument contiguous to the tuning-pins or nut end of finger-board.

Further objects and advantages of this invention will appear in the following description, and the novel features thereof will be particularly pointed out in the appended claims.

In the drawings, Figure 1 is a perspective View of a guitar provided with main and aux- 8o The bridge embodying my invention comprises a base or support 1, adapted to be seated in any suitable manner upon the body or sounding-board of the instrument and having a rear flange 2, provided with kerfs and notches 3, through which the strings 4 extend after leaving the tailpiece 5. Mounted upon this base or support are string-rests 6, which in the construction illustrated are disposed, respectively, in the planes of the strings, are

fitted in guides 7 for movement parallel with said strings, and are provided with shallow notches 8, forming string-seats. These rests maybe constructed of any suitable material, such as bone or the equivalent thereof, and

Fig. 4 is a similar view of one 85 in the construction illustrated they are made of cross-sectionally=dovetailed shape to fit in the cross sectionally dovetailed laterallyfianged guides 7.

In order to secure correspondence between the harmonic and normal or fretted octaves of a given string, the rest traversed by that string should be adjusted to provide such an exposed or operative length of the string as to compensate for the degree of elasticity thereof, the test, as above indicated, being made at the twelfth fret. Obviously the advantage of the adjustable rests resides in the fact that variations in the elasticities of two strings used in connection with the same rest may be compensated for by the performer when the given string is applied to the instrument. It will be understood that the tuning of the strings is accomplished independently of the adjustment of the rests; but the relative positions of the latter will compensate for the differences in elasticity of the strings at all tensions of the latter, and hence when the instrument is tuned to different pitches.

A further advantage of a bridge having movable string-rests constructed in accordance with my invention resides in the fact that it provides means for compensating for the warping of the neck of an instrument by reason of the strain applied thereto by the strings. It is well known that after an instrument has been in use for a considerable time the neck warps upwardly, thereby increasing the distance between the strings and the finger-board, and this action has the effect of destroying the relative pitches of strings when depressed into contact with the frets, or, in other words, destroys the perfection of the scales as produced by the instrument. This warping of the neck, however, can be compensated for by manually moving the string-rests toward the tailpiece, as will be readily understood from the foregoing description, to lengthen the exposed or operative portions of the strings to suit the increased distance between the strings and the finger-board.

The main bridge, which I have described and which is located, as in the ordinary practice, contiguous to the tailpiece of the instrument, is adapted to perform all of the necessary functions with regard to compensating for different elasticities of the strings; but I have found in practice that it is desirable under certain circumstances to employ an additional or auxiliary bridge 1, corresponding in construction with the main bridge above described and having string-rests adjustable parallel with the strings. This auxiliary bridge is designed to supplement the function of the main bridge and enable the performer to secure an accurate adjustment of the operative or exposed lengths of the several strings.

In practice I prefer, as above indicated, to construct the adjustable rests of bone or equivalent material fitted, as shown and described, in cross-sectionally dovetailed ways or guides consisting of flanged plates having upturned lateral edges inclining toward each other as they recede from the central or body portion of the plate, the peculiar advantage of this construction residing in the fact that, as the guides are unobstructed throughout, the rests may be moved throughout the lengths thereof and may be introduced thereinto through either end. Also it is obvious that the yielding quality'of the flanges or walls of the guideways is sufficient to retain the rests in their adjusted positions without other means of fastening. In other words, the frictional contact between the inner-surfaces of the flanges or walls of the guides and the side beveled surfaces of the rests is sufficient to maintain the latter at the desired adjustment in opposition to any tendency thereof to vary in position by reason of the vibration of the strings.

Various changes in the form, )roportion, and the minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of this invention.

Having described my invention, what I claim is 1. A bridge for stringed instruments having a base, and a plurality of parallel flanged guides forming ways having yielding side walls, and string-rests fitted in said ways be tween the side walls thereof for adjustment parallel with the strings and frictionally held in their adjusted positions by said walls, substantially as specified.

2. A. bridge for stringed instruments having a base, a plurality of independent guides having lateral upturned flanges, converging as they recede from the central or body portions of the guides, to form ways having yielding side walls, and cross-sectionally-dovetailed rests fitted in said ways between the side walls thereof for manual adjustment parallel with the strings, substantially as specified.

3. A bridge for stringed instruments having a base 1 provided with a rear kerfed or notched flange 2, a plurality of laterallyflanged yielding guides permanently secured to the base, respectively in alinement with the kerfs or notches of said base-flange, to form unobstructed ways having upwardlyconvergent side walls and open ends, and rests fitted for manual adjustment in said ways and held by the frictional contact of the walls thereof against accidental displacement, substantially as specified.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.

LINCOLN UTT.

WVitnesses:

W. E. MOCAUSLAND, H. C. WALLACE, Sr. 

